Supplementary Material

The relationship between changes in body weight and body mass index (BMI), and serum alanine aminotransferase (ALT) concentrations were assessed in subjects with these measurements taken at time intervals of 1-4 months (58%), 5-8 months (32%), 9-12 months (23%), and beyond one year after the initial visit with the pediatric gastroenterologist (23%). Supplementary Table 1 presents a comparison of subjects who were included in these analyses (Figures 2 and 3) with those subjects who did not have follow-up data. As expected, subjects who were monitored over time tended to have higher baseline serum ALT concentrations. Body weight and BMI status did not appear to a major determinant of patient follow up, although subjects with data available in the 5-8 month time interval had significantly greater baseline body weight (p=0.024).